I know this wasn't Larian's decision but I believe omitting alignment altogether would be a mistake. WoTC seems to have had it out for alignment since 4th ed where there was a great deal of backlash and criticism to the changes they made and they eventually backtracked, restoring the original axis. I am fine with it being downplayed but how would spells like detect alignment, protection from evil, and alignment restricted items work?
I think the argument for removing it is that not having alignment is somehow more realistic and allows more player freedom. My response to this is that in the real world good and evil are just social contructs but in a fantasy world, particularly the Forgotten Realms, they are real tangible, quantifiable forces. Fantasy evil isn't the same as real world evil. Of course, like everything else there are exceptions and good storytelling should always takes precedence over rules.
In short I believe the alignment axis is an important part of the game mechanically and lore wise and should be kept
